Dowel-pin.



L'T. GILMEH.

DOWEL PIN. APPLICATION FILED nc.2o. 1913.

. Patented Aug. 17, 1915.

FFQ

JOHN THORNTON GILMER, OF FULTON, ALABAMA.

DOWEIi-PIN.

Specification of Letters Patent.

Patented Aug. 17, 1915..

Application filed December 20, 1913. Serial No. 807,934.

to the meeting portions of the wood stock and driven home to hold thejoined elements in the desired relation without the necessity ofemploying glue or any other adhesive.

A further object is to provide a dowelpin of the class described whichis formed of metal and consists broadly in a tubular body portion havinga. number of longitudinally extending prongs projecting from itsterminals, which prongs are adapted to be spread outwardly and intoengagement with the material joined by means of separate spreading headswhich are insertible in the bores which have been previously formed inthe meeting portions of the united elements to receive the tubular bodyportion.

A still further object is to provide a modified form of pin soconstructed that it is necessary to form a bore in only one of thejoined elements.

,A yet further object is to construct the dowel-pin with such regard toproportion, arrangement and number of parts that it may be cheaplymanufacutr'ed, will be durable and efficient in its action, and may beapplied to the meeting portions of the furniture or other article with aminimum expenditure of time and labor.

The above and additionalobjects are accomplished by such means as areillustrated in the accompanying drawings, described in; the followingspecification, and then more particularly pointed out in the claimswhich are appended hereto and form a part of this application.

With reference to the drawings, wherein there hasbeen illustrated thepreferred embodiment of this invention as it is reduced I to practice,and throughout the several views ofwhich. similar reference numeralsdesignate corresponding parts, Figure 1 is a sectional view of twoblocks or boards showing the dowel-pin in position before the boardshave been urged toward one another to spread the prongs of the tubularbody member and to dispose the body member in the receiving bores formedin the boards; Fig. 2 1s a sectional view illustrating the boards injoined position, and showing the prongs as they are disposed afterhaving been driven inwardly against the removable spreading heads; Fig.2 is a detail view in longitudinal section of one terminal of the bodyportion of the dowel pin, showing a fragmentary perspective of the headmember in the position it assumes when the prongs have been spread. Fig.3 is a sectional view showing two boards or blocks joined by means of amodified form of pin; Fig. A: is a perspective view showing the completedowel-pin and removable spreading heads of the preferred embodiment ofthe invention; and Fig. 5 is a perspective view illustrating themodified form of pin.

Proceeding now to the description of the drawings, and referringparticularly to Fig. 4 in which the dowel-pin of the preferredembodiment is illustrated in detail, the nun eral 10 designates the bodyportion of the pm. The body portion 10 is formed of any type of metal,and i preferably tubular in s ape.

At each terminal of the body portion 10 are formed a number oflongitudinally directed outwardly extending prongs, indicated at 11.prongs are beveled upwardly so that the prongs will be spread when theyare driven into engagement with the removable head member 12, as will behereinafter more fully disclosed.

In the preferred embodiment of the invention, three prongs are formed ateach terminal of the body member 10, but it is, of course, obvious that,if so desired, a greater or less number may be provided withoutdeparting from the spirit of this invention. In manufacturing the bodyportion 10 and its integral prongs 11, it has been found expedient tofashion the device from a sheet of metal and to then roll the sheetabout a tubular mold. If found expedient, however, the pins may be castin the wellk'nown manner.

The spreading heads 12 are concaved at terminal is formed an annularflange, as

The inner faces of these i indicated at 14 and 15. The member 14 is ofless diameter than the member .115, being so formed for a purpose to bedescribed hereinafter. The middle portion 13 which, as previouslystated, is conceived merges into the members 14: and 15 so that when thebeveled prongs of the embers 11 have been forced past the smaller flange14:, they will engage against the curved face ofthe middle ortion 13 andwill "ride upwardly therealong until they meet the enlarged flange 15which will act to spread the prongs.

The actual'construction of the preferred form of dowel-pin being thusdescribed, reference will now be had particularly to Figs. 1 and 2, inwhichthe preferred form of pin 7 is shown in assembled position. It willbe noted upon reference to Fig. -1 that the boards or blocks Aand B areprovided at their meeting edges with inwardly extending bores 16 and 17The bores 16 and 17 are adapted to receive the body portion 10 of thepin when the boards A and B have been urged together with their adjacentedges contacting, as in Fig. 2.

In applying the dowel-pin to the members A and B, the heads 12 are firstdisposed in v the bores 16 and 17 and the pin is then positioned betweenthe adjacent edges of the boards with the prongs 11 extending into theopenings 16 and 17. -The members A and B are then urged toward eachother to bring their adjacent'edges into contact, as in Fig. 2. It willbe noted upon reference to this figure that as the boards are urgedtogether the prongs 11 will engage the flanges 15 of the spreading head,and will be directed upwardly and outwardly so that the body portion 10of the dowel-pin will be held against movement in either direction, andthe two boards or blocks A and B will, consequently, be securely joined.

'Coming now to the description of the modified form of the invention,and referring particularly to Fig. 5, thenumeral 18 designates the bodyportion of. the pin.

This body portion, which is substantially identical with the bodyportion 10 of the preferred embodiment, is similarly equipped withprongs 19. These prongs 19 are, however, formed on only one terminal ofthe body portion 18, the other terminal of the member 18' being equippedwith the screwshank 20. A head 21 similar to the member 12 of thepreferred form is provided to spread the prongs 19 when the modifiedform of dowel-pin is applied to'the two meeting portions of a pair ofboards, as illustrated in Fig. 3. In applying this modified form of pinto the boards C and D,

the screw-shank 20 is first threaded into the member C, and the headmember 21 is then positioned in a bore which is formed in the otherboard. The body portion 18 is then inserted in the bore, and the membersC and of the prongs,

to Fig. 1, this member serves to prevent the inward yielding of theprongs when the head members are being driven inwardly. It is to benoted that the head members are provided with two flanges, one of whichserves to guide the prongs and prevent the inward flexing thereof andthe other of which serves to spread the terminals of the prongs when thecontiguous members, to which the joint is applied, are being driventogether.

In conclusion, it is desirable to direct attention to the fact that thedowel-pin of this invention is.v relatively simple in its construction,but is so formed that it may be quickly and readily applied to articlesof furniture or the like to securely hold the meeting portions .of anytwo separate elements in assembled relation.

In reduction to practice, it has been found that the form of thisinvention illustrated in the drawings, andreferred to in the abovedescription as the preferred embodi ment, is the most eflicient andpractical; yet realizing that the conditions concurrent with theadoption of this device will necessarily vary, it is desired toemphasize the fact that various minor changes in details ofconstruction, arrangement of parts may be resorted to, when required,without sacrificing any of the advanta es of this invention, as definedin the appen ed claims.

What is claimed is 1. A dowel pin including a tubular body member,prongs formed at the terminals thereof, and a separate head member forspreading the prongs, said head member having a reduced inner terminal.adapted to be freely received within the tubular body member, a concaveintermediate portion adapted for engagement with the free ends and anenlarged outer terminal, the outer terminal of the member being ofgreater diameter than the diameter of the tubular body member.

2. A dowel pin including a tubular body" member, prongs formed at theterminals thereof, and a head member engageable with the prongs forspreading the prongs, said head member including a reduced annularflange formed at its one end, an enlarged annular flange formed at itsother end, and a concave portion connecting the flanges, said concaveportion merging into the enlarged flange and being of a clrcumfenence atone end greater than the distance between the and proportion I prongswhereby the (prongs may engage the concave surface an be deflectedthereby, said reduced flan e being of a diameter less than the internadiameter of the tubular .ter of the tu ular bodgemember, reduced flangemay body member, said enlarged flange being of a diameter member, prongsformed at the terminals thereof, and a separate head member forspreading the prongs, said head member having a reduced annular flangeformed at its. inner terminal, an enlarged annular flange formed at itsouter terminal, and a concave portion connecting the flanges, saidreduced flange being insertible between the prongs and being engageablewith the inner edges thereof for holding the prongs against inwardflexing when the terminals of the prongs are engaged with the enlargedflange and s read thereby.

4. dowel pin including a tubular body member, prongs formed at theterminals thereof, the terminals ofthe prongs being beveled from theirinner toward their outer surface, and a separate head member forseparating the prongs, said head member having a reduced annular flangeformed at its inner terminal and an enlarged annular outwardly beveledflange formed at its outer terminal, and a concave ortion connecting theflanges, said reduced flange being insertible between the prongs andbeing engageable with the inner edges thereof, said enlarged flangebeing engageable by the beveled terminals of the prongs for separatingthe same.

In testimony whereof I afiix my signature in presence of two witnesses.

JOHN THORNTON GILMEB. [13-8.]

lVitnesses E.'R. Hover, J. H. PETTY.

